Electronic audio systems have been known for many decades. Over those decades, such systems have undergone many changes in performance, function, and styling.
Many modern audio systems have a distributed system architecture. That is, the source or generator of the audio signal is physically separated from the sound-producing device. The audio source may for example be a radio receiver, a CD player, a handheld MP3 player or other similar portable music player, a mobile phone, or a tablet, laptop, or other type of computer. The sound-producing device may for example be a loudspeaker unit or headphone set or other head-mounted unit, including one or more earbud. The audio signal travels from the audio source to the sound-producing device via a given one of many known wired or wireless communication paths. The audio source formats the audio signal in a particular manner that can be “understood” (used) by the intended sound-producing device. Many different audio data formats are known, and are broadly separable into analog and digital formats, and/or wired or wireless formats. The format may be for example raw analog audio, or USB digital, or Bluetooth™, or Wi-Fi™ format. USB refers to the Universal Serial Bus standard, of which there are several versions including version 1.1, 2.0, and 3.0.
Many audio products today have most of the technology “built-in” to the product. For example, if someone wants to play music wirelessly from a Bluetooth-equipped smartphone to a headphone set, they would buy a Bluetooth headphone set, go through the setup process to establish a communication link from the smartphone to the headphone set, and then listen to the music generated by the smartphone remotely on the headphone set. In other cases the person may want to play the music on a wireless loudspeaker unit. If the person later replaces their smartphone with a new smartphone that does not support Bluetooth but does support a different wireless protocol, e.g., Wi-Fi or WiMAX, or that supports a new version of Bluetooth but not an older Bluetooth version resident on the loudspeaker or headphone, they would have to buy another headphone set or loudspeaker unit that had the new wireless protocol built-in. The originally purchased headphones or loudspeaker would have to be set aside, ultimately becoming obsolete.